Hydro-morphometrical analyses of sub-himalyan region in relation to small hydro-electric power

The choice of site for small hydropower potentials in the inaccessible tracts of Himalayan region is a difficult task by the conventional methods. Present work suggests a site for developing a multipurpose small reservoir under GIS framework, in the Sub Himalayan region, India. Scarcity of geographical, climate and statistical data was the main problem for development of seasonal precipitation and runoff modeling for assessing water potentials and identification of possible small-scale hydropower sites. Small hydropower potential is mainly regulated by head and its durability available at site depending upon capacity of the watershed, underlying the reservoir, to produce the runoff. The study reveals that the Bari-Ka- Khad watershed (BKW) can be considered as a suitable site of interest for small-scale hydropower installation. It is having maximum drainage density (7.45 km/km²) and maximum available relief ratio (0.12), which demonstrates better capacity to produce runoff. According to drainage texture of BKW (R_t?=?2.35), it come under coarse texture and higher values of Rho coefficient (ρ?=?3.65), suggesting higher hydrologic storage during rainfall and attenuation of effects of erosion during elevated discharge.     

Cogeneticity of Tavidar volcanics: Evidence by mixing line calculation

The Tavidar volcanics belong to a trachybasalt-trachyandesite-rhyolite association. Distribution and behavior of major and trace elements and field relationships indicate that intermediate and acidic volcanics of the area are cogenetic, whereas the basaltic phase is younger. Cogeneticity also is confirmed by the mixing line calculation. In the present case, instead of two pole mixing, three pole mixing between end members andesite, quartztrachyte, and rhyolite has been considered. Results show that a perfect linearity in data exists between andesites and quartztrachyte and between quartztrachyte and rhyolites.     

Shear wave velocity structure beneath the Archaean granites around Hyderabad, inferred from receiver function analysis

Broadband receiver functions abstracted from teleseismicP waveforms recorded by a 3-component Streckeisen seismograph at Hyderabad, have been inverted to constrain the shear velocity structure of the underlying crust. Receiver functions obtained from the Hyderabad records of both shallow and intermediate focus earthquakes lying in different station-event azimuths, show a remarkable coherence in arrival times and shapes of the significant shear wave phases:Ps, PpPs, PsPs/PpSs, indicating horizontal stratification within the limits of resolution. This is also supported by the relatively small observed amplitudes of the tangential component receiver functions which are less than 10% of the corresponding radial component. Results of several hundred inversions of stacked receiver functions from closely clustered events (within 2°), show that the crust beneath the Hyderabad granites has a thickness of 36 ± 1 km, consisting of a 10 km thick top layer in which shear wave velocity is 3.54 ± 0.07 km/sec, underlain by a 26 ± 1 km thick lower crust in which the shear wave velocity varies uniformly with a small gradient of 0.02 km/sec/km. The shear wave velocity at its base is 4.1 ± 0.05 km/sec, just above the moho transition zone which is constrained to be less than 4 km thick, overlying a 4.74 ±0.1 km/sec half space.     

Satellite based mapping and morphogenetic analysis of the landforms in the tertiary fold belts of parts of Tripura,India

In the present study, satellite-based mapping and morphogenetic analysis of eastern part of Tripura has been attempted. Landforms are delineated based on conjugate analysis of satellite-imaged and satellite-derived digital elevation data. Further, landforms were classified based on hierarchical three-tier classification system where genesis is used as a criteria to classify the landforms in the first level followed by nature of their dissection and the geometric forms of the landform in second and third level, respectively. During the analysis, it has been observed that most of the landforms are structural in origin and their orientations are guided by the geological lineaments although the variations in the dissection pattern of the landforms are related to the changes in the underlying lithology. The implementation of quantitative analysis using hypsometric integral and ruggedness index of geomorphic parameters indicates that the landforms are immature but have been evolving towards maturity.     

A transition from wood fuel to LPG and its impact on energy conservation and health in the Central Himalayas, India

The aim of the study was to evaluate the impacts of the transition from wood fuel to Liquefied Petroleum Gas(LPG) from energy use and health perspectives along an altitudinal gradient(viz.,lower altitude;middle altitude;and higher altitude) of the Central Himalayas.Empirical field study and questionnaire based survey was conducted forobtaining the data.A total of 20 households from each altitude were selected for obtaining reliable information on the actual quantity of fuelwood consumed.Of the 20 households,five households each based on the family size i.e.,small families(<4 members),medium(5-8 members) and large(>9 members) from all the altitudinal regions were selected.This was followed by an administration of a questionnaire on the quantity of fuelwood consumed.After the completion of the questionnaire survey,the data was validated using a weighted survey for the randomly selected households for obtaining precise information on the actual quantity of fuelwood consumed.Energy analysis is done with respect to the time spent on fuelwood collection and energy value of burning of per kg of fuelwood.Study indicates that declining biomass requirement from forests contributes significantly towards energy conservation,also has positive impact on human health.Per capita annual energy expenditure on collection of fuelwood is 752 MJ which is higher than any other activity in villages of Central Himalaya.The LPG substitution has contributed to energy saving which is equivalent to 2976-3,742 MJ per capita per year in middle and lower altitudes respectively.In the higher altitude the energy saving is calculated to be about 257 MJ per capita per year.Replacing fuelwood with LPG has made positive impact on society in terms of improving the health while reducing diseases that are caused due to indoor air pollution.     

Population Belongs on the Johannesburg Agenda

The forthcoming World Summit on Sustainable Development (WSSD) in Johannesburg (August 26-September 4, 2002) has been set by the United Nations to consider strategies toward sustainable development in all its dimensions. Hence, its mandate is broader than that of the Rio 1992 United Nations Conference on Environment and Development (UNCED). Population issues have so far been discussed in a separate series of World Population Conferences (Bucharest 1974, Mexico City 1984, Cairo 1994). With no new World Population Conference scheduled for 2004 and Johannesburg having a mandate that is stated to explicitly include social and economic aspects, population as a key component of sustainable development should figure prominently on the Johannesburg agenda. Yet, after the third of four preparatory meetings for Johannesburg (which ended in New York on April 5th), consideration of population is completely absent. The reasons for this are not entirely clear. We assume that they have to do with the fear of entering into political controversies over abortion. We are concerned that, despite its broader mandate, in most countries inputs to Johannesburg are being prepared mainly by environment ministries who have little experience in dealing with population questions. This revised version was published online in July 2006 with corrections to the Cover Date.     

Discrimination of low-grade magnetite ores using remote sensing techniques

The remote sensing community in geology is widely using the Multispectral Landsat Thematic Mapper (TM) data which has a wider choice of spectral bands (six between 0.45 and 2.35 μm, plus a thermal infrared channel 10.4-12.5 urn). These were evaluated for low-grade magnetite ores mapping over the high-grade granulite region of Kanjamalai area of Tamil Nadu state, India. The Fourier Transform Infrared (FTIR) spectroscopy data (0.4-4.0 μm) for powders of the magnetite ores exposed with granulite rock and published spectral reflectance data were used as guides in selecting TM band reflectance ratios, which maximize discrimination of magnetite ores on the basis of their respective mineralogies. The study shows that the weathering mineralogy of magnetite ores causes absorption features in their reflectance spectra which are particularly characteristic of the near infrared. Comparison of TM data with field and petrographic observations shows the presence of magnetite and aluminosilicate minerals & show strong absorption at 0.7-1 μ.m wavelength spectral region & increase in the product of two TM band ratios: band 5 (1.55-1.75 μm) to band 4 (0.76-0.9 μm) and band 3 (0.63-0.69 μm) to band 4 (0.76-0.9 μm). Various computer image enhancement and data extraction techniques such as interactive digital image classification techniques using color compositing stretched ratio, maximum likelihood and thresholding statistical approaches using Landsat TM data are used to map the low-grade magnetite ores of the granulite region. The field traverses and local verification enhanced to map the other rock types namely granulites and gneisses of the study area.